The Lost Children.(T. Don Hutto Residential Center)

In the summer of 1995, an Iranian man named Majid Yourdkhani allowed a friend to photocopy pages from "The Satanic Verses," the Salman Rushdie novel, at the small print shop that he owned in Tehran. Government agents arrested the friend and came looking for Majid, who secretly crossed the border to Turkey and then flew to Canada. In his haste, Majid was forced to leave behind his wife, Masomeh; for months afterward, Iranian government agents phoned her and said things like "If you aren't divorcing him, then you are supporting him, and we will therefore arrest you and torture you." That October, Masomeh also escaped from Iran and joined Majid in Toronto, where they lived for ten years. Majid worked in a pizza place, Masomeh in a coffee shop. She dressed and acted the way she liked--she is blond and pretty and partial to bright clothes and makeup, which she could never wear in public in Iran--and for a long time the Yourdkhanis felt they were safe from politics and the past. Their son, Kevin, was born in Toronto, in 1997, a Canadian citizen. He grew into a happy, affectionate kid, tall and sturdy with a shock of dark hair. He liked math and social studies, developed asthma but dealt with it, and shared with his mom a taste for goofy comedies, such as the "Mr. Bean" movies. In December, 2005, however, the Yourdkhanis learned that the Canadian government had denied their application for political asylum, and Majid, Masomeh, and Kevin were deported to Iran.

Upon their return, the Yourdkhanis say, Masomeh was imprisoned for a month, and Majid for six, and during that time he was beaten and tortured. After Majid was released, the family paid a smuggler twenty thousand dollars to procure false documents and arrange a series of flights that would return them to Canada.

Then, on the last leg of the journey, the family ran into someone else's bad luck. On February 4, 2007, during a flight from Georgetown, Guyana, to Toronto, a passenger had a heart attack and died, and the plane was forced to make an unscheduled stop in Puerto Rico. American immigration officials there ascertained that the Yourdkhanis' travel documents were fake. The Yourdkhanis begged to be allowed to continue on to Canada, but they were told that if they wanted asylum they would have to apply for it in the United States. They did so, and, five days later, became part of one of the more peculiar, and contested, recent experiments in American immigration policy. They were locked inside a former medium-security prison in a desolate patch of rural Texas: the T. Don Hutto Residential Center.

Hutto is one of two immigrant-detention facilities in America that house families--the other is in Berks County, Pennsylvania--and is the only one owned and run by a private prison company. The detention of immigrants is the fastest-growing form of incarceration in this country, and, with the support of the Bush Administration, it is becoming a lucrative business. At the end of 2006, some fourteen thousand people were in government custody for immigration-law violations, in a patchwork of detention arrangements, including space rented out by hundreds of local and state jails, and seven freestanding facilities run by private contractors. This number was up by seventy-nine per cent from the previous year, an increase that can be attributed, in large part, to the actions of Michael Chertoff, the Secretary of the Department of Homeland Security, which runs the Immigration and Customs Enforcement division. In 2005, Chertoff announced the end of "catch-and-release"--the long-standing practice of allowing immigrants caught without legal documents to remain free inside the country while they waited for an appearance in court. Since these illegal immigrants weren't monitored in any way, the rate of no-shows was predictably high, and the practice inflamed anti-immigrant sentiment.

Private companies began making inroads into the detention business in the nineteen-eighties, when the idea was in vogue that almost any private operation was inherently more efficient than a government one. The largest firm, Corrections Corporation of America, or C.C.A., was founded in 1983. But poor management and a series of well-publicized troubles--including riots at and escapes from prisons run by C.C.A.--dampened the initial excitement. In the nineties, C.C.A.'s bid to take over the entire prison system of Tennessee, where the company is based, failed; state legislators had grown skeptical. By the end of 2000, C.C.A.'s stock had hit an all-time low. When immigration detention started its precipitate climb following 9/11, private prison companies eagerly offered their empty beds, and the industry was revitalized.

One complication was that hundreds of children were among the immigrant detainees. Typically, kids had been sent to shelters, which allowed them to attend school, while parents were held at closed facilities. Nobody thought that it was good policy to separate parents from children--not immigration officials, not immigrant advocates, not Congress. In 2005, a report by the House Appropriations Committee expressed concern about "reports that children apprehended by D.H.S."--the Department of Homeland Security--"even as young as nursing infants, are being separated from their parents and placed in shelters." The committee also declared that children should not be placed in government custody unless their welfare was in question, and added that the Department of Homeland Security should "release families or use alternatives to detention" whenever possible. The report recommended a new alternative to detention known as the Intensive Supervision Appearance Program--which allows people awaiting disposition of their immigration cases to be released into the community, provided that they are closely tracked by means such as electronic monitoring bracelets, curfews, and regular contact with a caseworker. The government has since established pilot programs in twelve cities, and reports that more than ninety per cent of the people enrolled in them show up for their court dates. The immigration agency could have made a priority of putting families, especially asylum seekers, into such programs. Instead, it chose to house families in Hutto, which is owned and run by C.C.A. Families would be kept together, but it would mean they were incarcerated together.

When the Yourdkhanis were sent to Hutto last winter, the facility had been open for nine months, but few Americans knew of its existence. Hutto is in Taylor, Texas, a town of seventeen thousand, forty miles northeast of Austin, with a lot of boarded-up businesses on its main streets. A National Guard recruiting station is on the eastern side of town; a place that offers concealed-weapons training is at the opposite end. Hutto has more than five hundred beds, though the population fluctuates, and the facility appears never to have been at full capacity; about half the detainees are children. At the time the Yourdkhanis got there, many of the four hundred or so detainees were from Latin-American countries (these did not include Mexico, because Mexicans caught without documents are automatically sent home), and some of those were people who had come to the United States for economic reasons; that is, they were the kind of undocumented immigrants that most people probably think of when they hear of immigrants being rounded up somewhere in Texas. But a substantial number of the families were asylum seekers--people from Iraq, Somalia, Iran, Romania. Like the Yourdkhanis, they were people who said that they had been persecuted in their home countries, and many of them had passed the first test for achieving asylum in the United States--a so-called "credible fear"…